I installed a baffled plate a year or two back, i will warn you that those pan bolts love to strip so be gentle with those.
As for the regulator i know that racing beat sells a nice "race regulator" putting the pressure at 115 psi or so.. there are others that put it at about 80 psi at full rpm. You will have to shim the spring as well... the racing beat kit comes with shims and instructions... I went ahead and picked up a fresh spring from mazda... found it to be a different length then whatever the previous owner had in there, could have just been worn, but I was happy i replaced it.